The present invention relates to an air cleaner which is mounted to an engine compartment of a vehicle, is connected to an intake side of an engine, and is provided for removing dust contained in an intake air.
Conventionally, to reduce a space required at a time of attaching and detaching the filter within the engine compartment, there has been proposed a structure in which a filter is taken in and out along an axial direction with respect to the housing of the air cleaner, without opening and closing the housing.
For example, Japanese Laid-Open Patent Publication No. 2000-130272, Japanese Laid-Open Patent Publication No. 9-122417, and Japanese Laid-Open Utility Model Publication No. 6-63857 each disclose an air cleaner structured such as to allow a filter having a frame and an element supported to the frame to be taken in and out through an opening from an upper portion of a housing. In a state in which the filter is installed in the housing, a seal surface of the filter is joined to a seal surface of the housing.
In the structure described in Japanese Laid-Open Patent Publication No. 2000-130272, a rib protruding toward the seal surface of the housing than the seal surface of the filter is formed in a lower end of the frame of the filter. Since the rib is placed on the seal surface of the housing at a time of attaching and detaching the filter to and from the housing, the contact between the seal surface of the filter and the seal surface of the housing is suppressed. As a result, abrasion and deformation are prevented in the seal surface of the filter.
Further, in the structure described in Japanese Laid-Open Patent Publication No. 9-122417, a protrusion is located in an opposite side to the seal surface, in the lower end of the frame of the filter. Further, within the housing, there are formed an engagement groove portion engaging with the protrusion of the frame, and a guide wall for guiding the protrusion of the frame to the engagement groove portion. If the filter is inserted into the housing from the opening of the housing in a state of being inclined, the protrusion of the frame is moved along the guide wall of the housing so as to be engaged with the engagement groove portion. Thereafter, the filter is rotated from an inclined position to a vertical position around an engagement portion between the protrusion and the engagement groove portion, and the seal surface of the filter is joined to the seal surface of the housing.
Further, in the structure described in Japanese Laid-Open Utility Model Publication No. 6-63857, a protrusion protruding downward is formed in a lower end of the frame of the filter. An inclined surface is formed in a back surface of the protrusion. An engagement recess engaging with the protrusion of the frame is formed in a lower end of the housing. An inclined surface capable of engaging with the inclined surface of the protrusion of the frame is formed in the engagement recess. If the filter is inserted into the housing from the opening of the housing, the protrusion of the filter is engaged with the engagement recess of the housing. At this time, on the basis of the engagement between the inclined surface of the protrusion and the inclined surface of the engagement recess, the filter moves toward the seal surface of the housing, and the seal surface of the filter is joined to the seal surface of the housing.
However, in the conventional air cleaners, the following problems are generated. In the structured described in Japanese Laid-Open Patent Publication No. 2000-130272, the rib of the filter is placed on the seal surface of the housing at a time of attaching and detaching the filter to and from the housing. Accordingly, the seal surface of the housing tends to be damaged by the rib, and there is a risk that a defective seal is generated between the housing and the filter.
Further, in the structure described in Japanese Laid-Open Patent Publication No. 9-122417, the lower end of the seal surface of the filter slides with respect to the seal surface of the housing at a time of inserting the filter to the housing. Accordingly, each of the seal surfaces of the filter and the housing tends to be damaged.
Further, in the structure described in Japanese Laid-Open Utility Model Publication No. 6-63857, the protrusion only protrudes downward from the frame. In this structure, in the same manner as Japanese Laid-Open Patent Publication No. 9-122417, the seal surface of the filter slides on the seal surface within the housing at a time of attaching and detaching the filter to and from the housing. Accordingly, there is a risk that each of the seal surfaces of the filter and the housing is damaged and there is a risk that the defective seal is generated.
There is a case where the interior of the housing of the air cleaner comes to a negative pressure and the frame of the filter is bent inward, at a time of driving the engine. At this time, in the air cleaner described in each of the patent documents mentioned above, the seal portion of the filter is bent inward, the contact area with respect to the seal surface of the housing becomes small, and there is a risk that the seal portion of the filter comes off the seal surface of the housing. In this case, the defective seal is generated.